# Homework Help: Vector Problem

1. Sep 6, 2008

### Bryanaam

1. The problem statement, all variables and given/known data
A person is traveling (4.8 mph and 3.6 mph) in a South and East direction. If the person doubles speed in same directions what is the answer.. I have no idea how to solve this problem. Can i just multiply both vectors by 2

2. Relevant equations

3. The attempt at a solution
4.8 x 2 = 9.6 mph
3.6 x 2 = 7.2mph

2. Sep 6, 2008

### vociferous

I am not sure what answer they are looking for based on the given problem as you state it, but I would surmise that they want to know the velocity (that is, speed and direction) of the two vectors combined.

3. Sep 6, 2008

### Bryanaam

The answer would be in this format ( X speed in South; X speed in East)

4. Sep 6, 2008

### tiny-tim

Welcome to PF!

Hi Bryanaam! Welcome to PF!

Yes … if a vector is doubled, then its components are doubled.

(This is because vectors are from vector spaces, and every vector space has scalars (ordinary numbers, in this case), and they obey the distributive law, eg 2(A.B) = (2A).B )